@import "./common.scss"; //导入的语法

body{
    button {
        color: $error;
        @include border-radius;
        @include border(2px, solid, red)
    }
    a{
        @include border-radius;
    }
    ul{
        @include h-ul;
        @include border($w:2px, $s:dotted,$c: red)
    }

    div{
        border: 1px solid red;
        background-color: red;
    }

    span{
        @extend div;
        font-size: 20px;
        background-color: transparent;
    }
}